The goals of this subproject are to take a research program that has been strong and provide collaborative support with research intensive faculty from other campuses. The venom research program is at a stage in its development when it would benefit from collaboration with major universities with excellent facilities and faculty with expertise in molecular biology. The natural resistance of certain animals to snake venoms is well documented in the literature. These animals have antihemorrhagic and antiproteolytic factors in their sera which neutralize a wide variety of hemorrhagins found in many snake venoms. The research goals are to isolate and determine if antihemorrhagins in opossum serum could be used to neutralize venom in humans and other animals without causing complications. The objectives in the next five years are to focus on the following questions. (a) Can venom be used to increase the natural antihemorrhagin titer or stimulate antibody production in opossums? (b) What organ or tissues(s) in the opossum are producing antihemorrhagins? (c) Do other resistant animals (woodrats and Mexican ground squirrels) neutralize venom in the same way? (d) Can a non-animal assay such as an ELISA or western blot be used to screen for antihemorrhagins found in other resistant animals? (e) What is the smallest segment of the opossum antihemorrhagin that can neutralize the hemorrhagins found in snake venoms? (f) Will a smaller segment (less than 10,000 Daltons) neutralize venom without causing serum sickness or other anaphylactic problems in snakebite victims? (g) Does the smaller segment neutralize all seven hemorrhagins in C. atrox venom? (h) Do the seven hemorrhagins found in snake venom have a common active site that bind to the antihemorrhagins? (i) Do the antihemorrhagins found in other resistant animals bind and neutralize venom hemorrhagins in a similar manner? (j) Can DNA probes and primers be made by sequencing the N terminal end of antihemorrhagins? (k) Can these probes and primers be used to identify and clone antihemorrhagic genes and can the genes be expressed in E. coli? and (l) can the recombinant product (antihemorrhagin) be used to neutralize snake venoms? Two faculty from TAMUK will be working on the subproject II, and collaboration agreements with other universities have been established in the areas of molecular biology and immunohistology.